The present invention relates to electrical energy generation and can be used in devices with transportable and non-transportable electrical energy sources with high efficiency, high service life and short charging time.
Current sources of electrical energy use lead batteries which usually contain two grate plates of lead-antimony alloy, with the grades filled with a paste lead oxide mixed with water. Identical plates are immersed in a vertical position in electrolyte which is aqueous solution of sulphuric acid. As a result of a reaction, the lead oxide after a certain time is converted into lead sulphide. When electric current passes through the battery from an outside current source during charging, negative ions move to the anode and transform the lead sulphide into lead dioxide. Positive hydrogen ions move toward the cathode and reduce the lead sulphide to a metallic lead. When electric current passes through, the plate becomes asymmetrical. On one of the plates the lead sulphide on the negative pole is transformed into sponge lead, on the other plate the lead sulphide on the positive pole is transformed into lead dioxide, and the battery is charged. Thus, a galvanic pair is formed which can be a source of electric current. The electric motor source of such a battery with full charge is increased to two volt. When such a battery is connected as a source of electric current to an outside load, it will discharge and the processes take place in an opposite direction. At the end of the discharge, both plates are covered with identical layers of lead sulphide and the electric motor force drops to zero. However, in practice at the end of the discharge the electric motor discharge does not decrease lower than 1.85 volt, since the battery is destroyed at a greater charge. Usually batteries with electric motor force of 12 volts and not 2 volts are not utilized, since such a battery has an energy six times greater than that of the lead battery of two volts. In order to obtain the electromotive source of two 12 volts, six batteries are connected electrically with one another in series. The problems which occur in the battery of 12 volts are determined by those of each battery of two volts.
Capacity which can be obtained from the lead battery, depends on the quantity and porosity of the positive active mass, on the quantity and porosity of the negative active mass, and the quantity and concentration of electrolyte as well as on the construction of the battery. The conventional batteries have a relatively short service time, low capacity and a long time of battery discharge, low weight of positive active mass when compared with the weight of the grates composed of the alloy, in which the positive active mass is accommodated. In the service life of the lead battery depends on service life of positive great plates due to the corrosion of metal grates and melting of positive active mass. The grate plates of the positive electrode have a direct contract with the electrolytes. When electric current passes through the battery during charging, negative ions SO4xe2x88x92xe2x88x92xe2x88x92Oxe2x88x92xe2x88x92 moved toward the metal grate and actively interact with the metal of the grates and the grates are destroyed. Another factor which limits the service life of the batteries is melting (reduction) of positive active mass PbO2. The service lives can be increased by creating in the positive active mass of a porous structure. However, the melting of the positive active mass is so intense that the battery becomes inoperative in a short time. Even with a low quantity of pores, this negative effect takes place. The increase of charge current also leads for formation of porous BO2 which reduces the service life of the batteries. Because of this, the value of the charging current in such batteries is limited and the time of charging is very long.
In order to reduce melting of the positive active mass, the battery is provided with special separators, which however do not complete prevent the melting of positive active mass, and on the other hand reduce the capacity of the battery. The separators also increase the inner ohmic resistance of the battery, makes difficult access of acid to the plates, and replaces a substantial volume of acid and therefore reduces its quantity in the battery. The grater is current density of battery discharge, the grater is voltage drop during passage of current along an inner surface through the separators, the grater part of common voltage dropped without use. During discharge with a great current density, a consumption of acid per time unit is high. Due to the diffusion the required quantity of acid does not pass through the pores of the separator, discharge is provided mainly by the stored acid in the pores of the plate. However, the quantity of the pores in the positive active mass is low and as a result the capacity of the battery is low. Thus, the melting of the positive active mass is a factor which limits the service life and capacity of known lead batteries.
U.S. Pat. No. 4,964,878 discloses a battery in which the plates are located horizontally. However, the battery contains the same elements of conventional batteries, in which the plates are located vertically and which negatively affect the parameters of the battery. The battery disclosed in this reference also has grates of lead-antimoni alloy with positive active mass in its cells. The separators are utilized. The active mass, which is even worse than in known batteries is located directly on the separator of porous material. The service life of this battery is limited by corrosion of the grates which loose its strength and increases electrical resistance. The positive mass located in the corroded cells is also melted. In this battery there is even more intense melting of the positive active mass, and the capacity of the battery as well as the service life of the battery is reduced. Therefore this battery is not possible to use a loose positive mass as in conventional batteries. In an attempt to reduce the degree of penetration of the positive active mass through the pores of the separator, the reference proposes to use separators in three layers. This however reduces the capacity of the battery, increases the inner resistance, makes difficult access of sulphuric acid to the plates, replaces a substantial volume of sulphuric acid.
Accordingly, it is an object of the present invention to provide an electrical battery of the above mentioned type, which avoids the disadvantages of the prior art.
In keeping with these objects and with others which will become apparent hereinafter, one feature of present invention resides, briefly stated, in an electrical battery which has a positive active mass accommodated in a horizontally located cuvette with an open upper surface, a negative active mass located in another horizontal cuvette and having an open lower surface, with the second cuvette located on top of the first cuvette, and the cuvettes are accommodated in an electrolyte, and the battery contains a plurality of pairs of the above mentioned cuvettes, and the pairs are connected electrically in series with one another.
Preferably, the cuvettes are composed with plastic and do not interact with a solution of electrolytes. A bottom of the plastic cuvette for the negative active mass is a grate with a small wall size when compared with a whole size to provide a free penetration of electrolyte through the bottom into a space between the positive active mass and the negative active mass. The sickness of the great-like bottom of the cuvette for negative active mass determines a distance between the upper surface of the positive active mass and the lower surface of the negative active mass. The cuvettes have relatively thick peripheral vertical walls and therefore are stably arranged on one another to form a single block, while the bottom is thin to provide a low weight. The utilized plastic material reduces the weight of the battery.
The lead plate of the negative electrode has a system of windows, in which two windows are filled with paste for forming the negative active mass and the third one is free for passage of electrolytes into the space of the positive active mass and the negative active mass and flows under the windows filled with the paste from all sides.
A great quantity of the electrolyte for the lower pair of the active mass is determined by a space above these pairs, which is formed by high legs of the upper cuvette with the positive active mass which stand on the cuvette with positive active mass of the lower pair.
Both positive and negative active mass has admixtures providing expanding action in order to form during charging and discharging a loose, porous structure of the active mass, to increase the capacity of the battery. A substantial quantity of electrolyte under the cuvette with the positive active mass and easiness of its penetration into a space between the lower positive and negative active mass together with the loose porous structure of the active masses provides a greater capacity of the battery, while a small space between the positive and negative active masses determined by the thickness of the great-like cuvette bottom for the negative active mass, provides a low inner resistance to current passing through electrolytes between the upper surface of the positive active mass, between the upper working surface of the positive active mass and the lower working surface of the negative active mass. Current does not pass through the great quantity of electrolytes located under the cuvette with the legs with the positive active mass.
The plastic cuvette which accommodates the positive active mass is located horizontally and therefore melting of the positive active mass is completely excluded. As a result, it is possible to operate with high currents which creates loose porous structure for the positive active mass and provides a great capacity of the battery. The possibility to charge the battery with high currents results in a short charging time of 15-20 minutes. Since the cuvette is located horizontally, the melting of the positive active mass is excluded and it is therefore possible to introduce admixtures for expansion purposes, which during charging and discharging produce loose porous structure with resulting high capacity of the battery.
The horizontally located cuvettes which are assembled in the block and tied together by a plastic belt are introduced into a vessel of acid-resistance material, electrolyte is poured into it and the vessel is disclosed in the covered and hermetized.
Each cuvette on the periphery has several vertical recesses, so that when they are assembled in a block, a vertical passage going from top to bottom is provided between the block and a lower wall of the vessel. Electrolyte freely flows through this passages to the whole depth of the block. For electrical current at the bottom of the cuvette under the layer of the positive active mass, a lead collector is located, and the collector does not have a direct contact with electrolyte. On the other hand, the whole positive active mass participates in the process of charging-discharging, since electric current which passes through the electrolyte and collector also passes through the whole thickness of the loose porous positive active mass.
In order to take voltage from the collector for positive active mass and for charging and discharging from the exterior current source, a contact electrode plus is utilized. For withdrawing voltage from the collector for the negative active mass and for and charging and discharging from an external current source, a contact electrode minus is utilized.
In order to increase the out voltage, the subsequent pairs in the horizontal cuvettes located one above the other are connected in series with each other by contact electrodes.
The novel features which are considered as characteristic for the present invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.